Single header multiple-pass superheater



June 14, 1932. c. s. TURNER I SINGLE HEADER MULTIPLE PASS SUPERHEATER 4Sheets-Sheet 1 Filed Dec. 13. 1928 INVENTOR. am 67 M A TTORNEYS.

June 14, 1932. c, s TURNER 1,863,174

SINGLE HEADER MULTIPLE PASS SUPERHEATER Filed Dec; 13, 1928 4Sheets-Sheet 2 FIG 3.

IN V EN TOR.

612M294 U a'w u/a BY A TTORN E YS.

Juhe 14,- 1932. a T RNE 1,863,174

SINGLE HEADER MULTIPLE PASS SUPEHHEATER Filed Dec. 15, 1928 4Sheets-Sheet 3 IN VEN TOR.

Maw

. I BQ Z W A TTORNEYS.

June 14, 1932. c. s. TURNER 1,863,174

SINGLE HEADER MULTIPLE PASS SUPERHE ATER Filed Dec. 13, 1928 4Sheets-Sheet 4 IN V EN TOR.

A TTORNEYS.

Patented June 14, 1932 UNITED STATES PATENT OFFICE CHARLES S. TURNER, OFDETROIT, MICHIGAN SINGLE HEADER MULTIPLE-PASS SUPERHEATER This inventionrelates to boiler superheaters, and has for its object improvementsparticularly directed to a single header multiplepass type ofsuperheaters. The principal objections to the constructions of thisgeneral type heretofore used have been that the tubes connecting thesteam drum with the discharge header have fared unequally inthe matterof the distribution of the steam pressure intended to be transmittedthrough them. In other words, certain ones of the series of pipes, moreadvantageously positioned relatively to the point of entrance of thesteam have drawn and transmitted a greater amount of steam pressure thanothers less advantageously located. Aslong as the method of attachingthe inlet and outlet ends of the steam pipes in a row along the wall ofthe steam drum is followed, there seems to be no adequate way ofovercoming this trouble, which my experience leads meto believe is dueto the lateral motion of the steam along the axis of the header takingplace in the headers, rather than in the tubes. Furthermore, in aneffort to increase the steam-treating capacity or linear extent of theindividual tubin sections, resort has been had to multiple or interiorloopings thereof, that is, lo-

cating several of the constituent sections of a single tubing unitwithin the same plane as viewed transversely of the steam drum. Thishas, however, proved highly objectionable in practice, in that in case aleak occurs 1n any of these interior curvatures of the pipe, it isnecessary to disassemble an inconveniently large proportion of theuninjured units on either side in order to afford access to the damagedpipe. Both of these objections I have overcome in the improvedconstruction herein illustrated in the figures of drawings, whereinFigure 1 is an elevational view of the simplest embodiment ofmy'improved construction, namely a plural connection between two steamdrums or headers with the pipes spacedly arranged lengthwise of the axisthereof.

Figure 2 is a sectional plan view thereof taken along the line 2-2 ofFigure 1 and 'therethrough from the steam drum to the discharge header.

Figure 5 is an elevational View similar to Figure 1, embodying aslightly variant contouring of the pipe sections.

Figure 6 is a plan view of this modified torm shown in Figure 5, takenfrom above.

Figure 7 is an elevational and partly diagrammatic sectional view of asingle series of pipe curvatures in the form of apparatus shown inFigure 5.

Figure 8, which is a perspective, is designed to bring out the sequenceand relation of the constituent sections of a single pipe unit fromsteam drum to header in the "form of apparatus shown in Figure 5.

Figure 9 is a side elevational view of this modified form includedwithin the superheater space of a steam boiler, embodying a plurality ofsections taken one within. the other, this view being taken from aposition looking lengthwise of the steam drum, in the same manner thatFigure 3 is illustrative of a single unit of the type of steam pipingunits employed in Figure 1.

It is my belief, based on my experience with various kinds ofsuperheating apparatus, that a large proportion of the operativeshortcomings of such equipment in the past has been due to undue lateralor lengthwise travel of the steam in the receiving drum or header,caused in turn by an inequality of the feed into it or" the steam fromthe steam drum. This I propose to remedy, as brought out in Figure 1 byproviding a single feeding pipe or series of pipes as B, leading fromthe steam source such as an ordinary steam drum A, to laterally locatedpositions of entrance into the lower header Z, extending along a lineparallel with the axis thereof, and with oppositely positioned dischargepipes, one outlet tube being directly opposite each inlet tube (thisfeature is clearly shown in Figure 2) employed in similar number to thepipes A for leading the steam into i the discharge header. For'smallcapacity installations this simple arrangement is in many cases adequatefor accomplishing the avoidance of inequalities in the distribution ofsteam in such an apparatus. But for large power plant uses anelaboration or extension of'this basic idea of avoiding cross orconflicting lines of steam travel becomes advisable, and ideas'as to oneform of such an apparatus are embodied in Figures 1, 3, and 9, wherein Aindicates an ordinary steam drum supported in any desired manner asbetween uprights A, the ordinary water level whereof is indicated withparticular clearness in F igure 3, as well as by the dotted line ainFigure 1. Above this level, so as to lead into the interior of thesteam drum, at a point definitely thereabove,

are tapped a series of pipe sections-B, each H of which leads downwardlytherefrom in sub- 7 stantially parallel relation to connection with theheader Z, similarly leading into the upper ortion thereof as at Z) inFigures 1 and 3. It will be noted that in the construction illustratedin Figure 1 these several connecting pipes B occupy illustratively onlyabout onefourth of the linear extent of said header Z. Just to the rightof this series of pipes is positioned, in the header Z, a diaphragm Lwhich confines the steam transmitted there- 'into through the pipes B tothe correspondshaped pipe sections D, of the same number ,as thosecomposing the series B ust mentioned, each one of the inlet tubes Bopening into its chamber opposite a corresponding outlet tube of theseries D. Each one of the outlet tubes D is directly opposite acorresponding inlet tube of the series B. These U-shaped pipe sectionsextend over the lower drum section C and angularly with reference to thelengthwise axis thereof to inlet con.- nection with the next diaphragmbounded lower drum section E whose top portion they enter in the samemanner as did the pipes B into the drum section 0. Similarly from theother side of the top portion of the. lower header section or header Eanother set of U-shapedpipe sections, as F, leads therefrom, each outlettube being directly opposite a corresponding inlet tube, and extendsoutwardly and upwardly in a loop for the absorption of heat, similarlyto section-D; its course being-parallelthereto, the tubes returning tothe next'se'ction G of the header which is spaced from the section E, bythe diaphragm M. From the far side of the upper portion of the header Z,as viewed in Figure 1, and from the upper side thereof .as viewed inFigure 2, another series of U- shaped pipe sections as H leads, againarching over the header Z parallel to the tubes in sections D and F, andreturning similarly to connection therewith in its chamber I which isspaced from the next previous section G by the diaphragm N. Then fromthe far side of the header Z as viewed in Figure 1, and the upper sidethereof as Viewed in F igure 2, another series of pipe sections Jextends from the chamber I of the lower drum Z each outlet beingopposite the corresponding inlet to connection with the discharge headerK, which for clearness of illustration is shown in Figure 1 aspositioned just below the steam drum A, Any number of such pipe sectionsand diaphragm-isolated header units may be employed, according'to thedesigned capacity of the particular apparatus. In each case it will benoted that two highly desirable results are secured: the limitation ofthe possible lateral travel of the steam lengthwise of the header Z, dueto the presence of the several diaphragms or partitions L, M and N, andthe assurance that the steam, on emerging from any one of the'pipes ofseries B, for example, into the header C, finds ready, and directlyoppositely positioned egress means through the correspondinglypositioned outlet pipes of the U-shaped series D, thus avoiding apossible crossing of the steam fiowage lines or an undue bleeding ofsome of the pipes of that series by one or ,more of its companion pipes,such as would result if no restriction were placed upon the degreeoflateral travel of the steam within the drum as it emerges from theseveral pipes of the series B. This guiding restriction or limitationupon the possible paths of travel of the steam prevails both as to theprinciple and the structure employed to effect it throughout the severaldiaphragm-formed chambers and their appurtenant and connecting U-shapedpipe sections. I

- I thus provide in either of the forms of construction illustrated inFigures 1 to 3, or

in either of the modified forms of construc tion hereinafter to bediscussed, a grouping of the pipe sections within a relatively limitedextent at several points along the length of the header Z, so'that eventhough there be slight variation in the steam pressure transmitted tothe several component units of the first pipe series B, any inequalitythereof is confined and redistributed within the first section C, sothat upon egress of the been the case if somelinequality prevailedthrough the various pipe sections of the series B. This equalization iscontinued in the direction of further progress toward uniformity duringthe transmission of steam from the header section E and through thepipes of the series F into the next header section G, and so on, so thatthroughout the riser pipe system an even distribution of the steampressure among the constituent pipe sections has been maintained.

In the modified form of piping sections illustrated in Figures 6, 7 and8, the same principles have been followed as regards isolation of thesteam in the several sections of the header I and the oppositepositioning of the inlet and outlet pipes of each section. In this formsteam entering from the drum P proceeds through the pipe sections ofseries Q, into the first diaphragm-isolated section R of the header I,thence through the riser tubes of the series S into the next section Tof the header I, thence through the next riser sections U to the thirdsection V of the header I, thence through the next series of risersection tubes W to the last diaphragm-isolated section X of the header,and thence through the riser pipes Y to the discharge header 0. This isbrought out diagrammatically as to a single pipe of each of the seriesdescribed in Figure 7, the several diaphragms or partitions shown inthat figure as well as in Figures 6 and 8 being designated as L, M andN, since they perform the same subdividing function as to the lower drumZ as a Whole as do the diaphragms L, M, and N in Figures 1 and 2.

In Figure 9 I have illustrated a modified form of construction adaptedespecially to overcome the second one of the objections to previousapparatus noted in the introductory paragraph hereof, to-wit, theprovision within the same vertical plane of an added or supplementalnumber of component pipe sections for each of the riser units which goto make up a series of pipes such as D, F, and H in Figure 1, in orderto provide a greater total of piping surface between the headersections. It will be obvious that the plane of any one of these sectionsthus constituted will as a whole lie at a slightly acute or obtuse anglerelatively to either the lengthwise axis of the steam drums A or Z, orto the plane of Figure l, for example, because of each of the U- shapedriser pipe sections therein illustrated extending angularly from oneside of, for example, the header section C, to the other side of thenext header section as E. Thus the element designated P in this figurecorresponds in position and function with the drum P of Figure 6, anddirectly behind it, as viewed in this figure would be located adischarge header corresponding to element 0 in Figure 6; the pipesections B, B and B would correspond to one pipe of the riser section Q,of Figure 6; and the lower drum C would correspond with thecorresponding structural and functional element I therein.

But in order to provide additional linear extent per riser section unit,without involving undue height of the apparatus as a whole, each groupof the first of the pipe series corresponding, for example, to theseries B of Figure 1, has three egress sections as B, B and B curved inposition for the passage of the steam through them and theircorresponding header, as C before it can go further and into the egresspipes D and D corresponding to the series D of Figure 1; each of thesesupplemental pipe sections being individually removable in case of thebursting or leakage of any one, it may be removed or repaired with aminimum of effort and displacement of adjoining parts.

What I claim is:

1. In a boiler superheater, in combination with a steam drum and aseries of discharge pipes leading therefrom, a plurally chamberedsuperheater header into one section of which said discharge pipes leadin a direction substantially perpendicular to the lengthwise axisthereof, a plurality of series of generally U-shaped pip-e sectionsconnecting each of the chambers in the header with the chamberadjoining, the tubes in each case leading into and from opposite sidesof the several chambers in substantial lateral alignment with eachother.

2. In a boiler superheater, the combination with a steam drum and aseries of discharge pipes leading therefrom, of a plurally chamberedheader into a side of one chamber of which said discharge pipes lead, aplurality of series of U-shaped tube sections each member of each seriesof which leads from connection with one of the chambers in said headerto connection with the adjoining chamber,

the several tubes connecting with each chamher in oppositely disposedportions thereof, and the inlet and outlet tubes being substantiallylaterally aligned in planes normal to the axis of the header.

3. In a boiler superheater, in combination 3 with a plurally chamberedheader, tubes connecting the chambers in series and so arranged thattheir inlets lead into one side of each of the intermediate of saidchambers and their outlets therefrom are arranged in substantialalignment with each inlet in a plane normal to the axis of the header.

In testimony whereof I sign this specification.

CHARLES S. TURNER.

